Toxic metals in tobacco smoke present a significant health risk. (H. Milnerowicz et al., 13 Int. J. Occup. Med. Environ. Health 185 (2000)). Metals such as lead, cadmium, arsenic, and tin have a relatively high transfer rate from tobacco into smoke. (V. Krivan, et al., 348 Fresenius J. Anal. Chem. 218 (1994)). These metals are known to be carcinogens, nephrotoxins, hepatotoxins and neurotoxins and can persist in the body for long periods of time. The total concentrations of metals in cigarette and tobacco smoke have been well established. (K. Kalcker, et al., 21 Sci. Total Environ. 128 (1993); W. Torjussen, et al., 5 J. Environ. Monit. 198 (2003)). However, it has been recognized that the total metal concentration is not sufficient to evaluate the impact of these metals on the environment and on human health. (S. Rapsomanikis, 119 Analyst (1994)). It is the specific physiochemical form of the metal that governs its toxicity, bioavailability, and its potential for bioconversion and bioaccumulation. In the case of tobacco smoke the relative abundances of metals species, particularly organometals species, are unknown. By establishing the chemical species of metals in tobacco smoke, the risks associated with inhalation of these compounds can be evaluated. This requires the development of an analytical technique for speciation of metals in the tobacco smoke.
Speciation methods are usually based on hyphenated techniques combining a chromatographic separation method with an element specific detection system, such as atomic absorption spectrometry (AAS), atomic emission spectroscopy (AES) or inductively coupled plasma-mass spectrometer (inductively coupled plasma mass spectrophotometer). Among the various speciation methods, gas chromatography with inductively coupled plasma-mass spectrometer (inductively coupled plasma mass spectrophotometer) has been increasingly applied as a means of speciation analysis for organometals in different environmental samples. (T. De Smaele, et al., 50 Spetrochimica Acta Part B 1409 (1995)). Chromatographic separation is ideally suited to complicated sample matrices and low analyte abundances; it separates compounds in complex mixtures based on their molecular size, boiling point and polarity. State-of-the-art dynamic reaction cell (DRC) inductively coupled plasma mass spectrophotometer provides superior sensitivities for metals and the capacity for simultaneous multi-element determination.
Coupling of a gas chromatograph to an inductively coupled plasma mass spectrophotometer originated with Van Loon et al., 41 Appl. Spectros. 66 (1987); J. Van Loon, et al., 19 Spectrosc. Letters 1125 (1986)), but little was reported on the application of this instrument configuration during the subsequent five years. (B. Bouyssiere, infra, at 805). Since 1992, based on the need for a reliable method of speciating metals in environmental samples, more and more applications of gas chromatography-inductively coupled plasma mass spectrophotometer have been reported. The gas chromatography inductively coupled plasma mass spectrophotometer technique has been applied to speciation studies in atmospheric samples (A. V. Hirner et al., 8 Appl. Organometallic Chem. 65 (1994)) in natural waters (C. M. Tseng, et al., 2 J. Environ. Monit. 603 (2003)) and in solids, including atmospheric particulate matter. (I. A. Leal-Granadillo, et al., 21 Anal. Chim. Acta 423 (2000)). Despite the multi-element capabilities of the inductively coupled plasma mass spectrophotometer, all analytes have to be separable by the gas chromatography in order to be detected by the inductively coupled plasma mass spectrophotometer. The gas chromatography requires volatile species. However, those organometal compounds with boiling points higher than the maximum gas chromatography column temperature cannot be adequately separated and so cannot be studied using direct sample injection and gas chromatography inductively coupled plasma mass spectrophotometer analysis.